Pleotrichophorus patonkusellus Corpuz-Raros & E. F. Cook 1974

Pleotrichophorus patonkusellus

DIAGNOSIS.—This species can be readily distinguished from other species living on Achillea (viz., P. hottesi, P. patonkus, and P. pseudopatonkus) by the most numerous dorsofrontal setae (34.89 ± 2.45, n = 18 vs. 25 or fewer on said species). Its small body size (1.16–1.62, m = 1.38 mm long, n = 31), the presence of few sensoria on a.s.III (1–2, m = 1.15, n = 48), a mean co/ca ratio of about 8/10 (.80 ± .03, n = 33) and the short (.09–. 11 mm, m =.100, n = 24), stout, slightly convex-sided rostrum IV+V are also distinctive. It resembles P. parilis in the shape and size of rostrum IV+V but differs in having shorter hind ta–2 and thus a relatively larger rostrum IV+V/ hind ta–2 ratio, in having denser head setae, a smaller ratio of unguis to the base of a.s.VI, shorter cornicles and smaller body size. Other details of differences from P. parilis are given under that species.

DESCRIPTION.—Apterous Viviparous Female: Color in life unknown; cleared specimen pale with darker apices of rostrum and tibiae, entire tarsi, tips of a.s.IV and V, and remainder of antennae (flagellum dusky from tips of a.s.III in some specimens). Body 1.16–1.62 (1.38, n = 31) mm long, .34–.44 (.377, n = 30) mm wide across eyes. Head with rather well-developed frontal tubercles; mf 1–2p (usually 2), lf 3–4 on each tubercle, vlf 1p, df 28–45 (34.89 ± 2.45, n = 18), vf 6–8, pc 2p, ac 4–6, and md 2–4 (usually 3) on each side; dorsal setae widely funnel- to cone- or fan-shaped, mostly without stems except anterior ones in some specimens; ventral setae with vf and ac similarly expanded, funnel-shaped, rest blunt or slightly expanded; mf .0154–.0374 (.0310, n = 53) and mf .0264–.0440 (.0333, n = 38) mm long. Antennal segment I moderately produced mesodistally, rather densely imbricate, with 5–9 blunt or knobbed hairs aside from basal pointed one on dorsum. A.s.II with usually knobbed setae. A.s.III imbricate with short knobbed setae, longest about ⅓ basal diameter of segment, bearing 1–2 (1.15, n = 48) sensoria. A.s.IV slightly longer than a.s.VI, latter about ¾ length of a.s.III; unguis of a.s.VI averaging 4⅓ times (range of 3¾–5⅔ n = 36) length of base.

Tergum smooth on disk, becoming imbricate-spiculate caudally from about abd.s. 5; setae rather dense, short, widely expanded funnel- to fan-shaped. Cauda .15–.23 (.194, n = 20) mm long; elongate, constricted on basal ⅓, broadly rounded at apex; spiculate; with 2 lateral pairs and 1 posterodorsal setae. Cornicles .12–.19 (.153, n–37) mm long, ⅔ to subequal (.80 ± .03, n = 33) length of cauda; cylindrical, of uniform diameter or slightly thickened near bases; conspicuously imbricate-spiculate, wrinkled, spicules rather low and blunt but distinct. Legs with 3, 3, 3 hairs on first tarsal joints; hind tibiae .73–1.05 (.84, n = 44) and hind ta–2 .10–.14 (.118, n = 44) mm long. Rostrum IV+V .09–.11 (.10, n = 24) mm long, .71–1.00 times (.85 ± .03, n = 43) as long as second hind tarsal joint; rather stoutly triangular, sides past pl setae slightly convex; with 1 basal, 2 dorsal, and 3 lateral pairs of setae, al 2–3 times ml and pl setae in length.

Measurements (in mm) of holotype: B.L. 1.29, We .38; a.s.III .40 and .38, a.s.IV .31 and .32, a.s.V both .27, a.s.VI .12 + .53 and .13 + .55; cornicles both .16, cauda .17; hind tibiae .83 and .85, hind ta–2 .12 and .11, and rostrum IV+V .10.

Alate Viviparous Female: Unknown.

Sexuales: Unknown.

HOSTS.—Achillea millefolium and Achillea sp.; also collected on undetermined Artemisia and an unknown host.

DISTRIBUTION.—Aside from type-localities, Eden in northern, and Allen Canyon in southeastern Utah.

TYPES.—Holotype, apt.v.f., 3–VII–1967, Logan, Utah, GFK, on yarrow (Berlese-extracted); in U. Minn. coll. Paratypes: 14 apt.v.f. and 6 apt.ny., with same data as holotype (4 slides each in U. Minn, and GFK coll.; remaining slides in LACR coll.); and 9 apt.v.f., Logan Canyon, Utah, 15–VIII–1959, JOP, on Achillea millefolium (JOP coll.).

OTHER SPECIMENS EXAMINED.—2 apt.v.f., Eden, Utah, 28–VI–1955, GFK, by sweeping Artemisia (EOE coll.); and 9 apt.v.f., Allen Canyon, Utah, 26–VII–1956, GFK, on unknown host (EOE coll.).

Pleotrichophorus patonkus (Hottes and Frison)

Capitophorus patonkus Hottes and Frison, 1931:287–289 [type: al.v.f., Metropolis, Illinois, 17–IV–1930, Frison and Ross, on Achillea millefolium; slide no. 10786 in INHS coll.].

Pleotrichophorus patonkus (Hottes and Frison).—Hille Ris Lambers, 1953:115; 1966:605 [in part]; 1969:165 [in part].

DIAGNOSIS.—This species can be distinguished from P. pseudopatonkus by its longer (at least .12 mm vs. .09–.11), slender and acutely pointed rostrum IV+V, longer cornicles (.14–.21, m = .173, n = 12 vs. .09–. 14, m = .099, n = 60), relatively larger co/ca ratio (.62–.75, m = .67 ± .01, n = 12 vs. .31–67, m = .43 ± .02, n = 60) and the usual presence of sensoria on a.s.IV of viviparous alatae (0–5, m = 2.38, n = 11, and in 84.6% of segments). See further notes below and diagnosis under P. pseudopatonkus.

DESCRIPTION.—Apterous Viviparous Female: Cleared specimen with pale body; antennae dusky or pale brown on apices of a.s.III and IV and entire length of remaining segments; legs pale with tips of tibiae and entire tarsi darker. Body 1.67–1.86 (1.81, n = 6), .40–.47 (.447, n = 6) mm wide across the eyes. Head with moderately developed laterofrontal and mesofrontal tubercles; mf 1p with 1 sometimes added or missing, lf 2–3 on each side, vlf 1p, df 19–24 (21.00 ± 2.19, n = 6), vf 7–8, pc 2p, ac 4–5, md 2–3 on each side; dorsal setae basically funnel-shaped, anterior much longer, more distinctly stemmed, more narrowly expanded than posterior ones; ventral setae with vf and pc also funnel-shaped, remaining setae blunt or slightly widened apically; mf .0264–.0484 (.0358, n = 14) and df–1 .0396–.0484 (.0442, n = 10) mm long. Antennal segment I moderately produced on mesodistal margin, imbricate, with 4–8 knobbed setae in addition to basal pointed one on dorsum. A.s.II with knobbed setae. A.s.III imbricate; with small knobbed setae, longest about ⅓ basal diameter of segment; with 2–6 (4.43, n = 7) sensoria. A.s.IV about 8/10 and a.s.V about ¾ as long as a.s.III; unguis of a.s.VI 5½ to 5⅔ times (5.59, n = 4) as long as its base.

Tergum smooth on disk, becoming finely imbricate-spiculate from about abdominal segment 5; setae moderately dense, funnel- to cone-shaped, those on posterior 2 segments longer than those on disk. Cauda .22–.26 (.257, n = 6) mm long; stoutly elongate, constricted on basal 1/3 and broadly rounded at apex; spiculate; with 2 lateral pairs and 1 posterodorsal setae. Cornicles .14–.21 (.173, n = 12) mm long, .62–.73 times (.67 ± .01, n = 12) as long as cauda; cylindrical, with slightly thickened bases; imbricate-spiculate, wrinkled, spicules minute, blunt. Legs with 3, 3, 3 hairs on first tarsal joints; hind tibiae .79–1.11 (1.02) and hind ta–2 .11–.14 (.123) mm long. Rostrum IV+V .12–13 (.122, n = 6) mm long, subequal to second hind tarsal joint (range of .86–1.09 times, m = .99 ± .06, n = 10); rather slender, tapering to acute point, portion beyond pi setae about 2/5 its entire length; with 1 basal, 2 dorsal, and 3 lateral pairs of setae, al about 3 times ml and pl setae in length.

Alate Viviparous Female: Head and prothorax slightly sclerotic with darker brown ring around ocelli; mesothorax brown; abdomen membranous with light brown pleural and marginal sclerites; antennae with basal 2 segments dusky, flagellum from near bases of a.s.III brown; wing veins brown; apices of rostrum and tibiae, entire tarsi dark brown; cornicles slightly dusky. Morphologically much like apterous female, differing only as follows: df setae fewer (11–17, m = 13.82, n = 11); sensoria on a.s.III more numerous (11–21, m = 16.0, n = 13), usually also present on a.s.IV (0–5, m = 2.38, n = 13); abdomen with 2 transverse pleural bars on segments 1 to 4, 2 pairs on 5 and a pair of smaller, oval pleural sclerites on 6, all but segment 8 also with marginal thickenings; abdominal setae relatively sparser, longer, less expanded; cornicles armed with larger, more sharply pointed spicules.

Measurements (in mm) of 11 paratypes: B.L. 1.50–1.70 (1.64), We .38–.43 (.404); a.s.III .53–.59 (.570), a.s.IV .47–.53 (.499), a.s.V .41–.48 (.461), a.s.VI .13–.15 (.140) + .72–.90 (.802); cornicles .12–.18 (.151), cauda .23–.28 (.250); hind tibiae .98–1.23 (1.16), hind ta–2 .12–.14 (.129), rostrum IV+V .12–.13 (.124); mf .0220–.0374 (.0318) and df–1 .0330–.0462 (.0409). Proportions of a.s.III:IV: V, 1: .71–.96 (.87): .69–.88 (.81); VIu/VIb 5.146.29 (5.69); co/ca .48–.70 (.60); rostrum IV+V/ hind ta–2 .86–1.08 (.97).

Sexuales: Not seen. Description of oviparous female in Hottes and Frison (1931:288–289) probably refers to P. pseudopatonkus. The description of the male apparently refers to a mixture of P. patonkus and P. pseudopatonkus as the authors describe the beak as “varying in length, in some specimens reaching to the coxae of metathoracic legs and in others reaching only to mesothoracic legs.”

HOST.—Achillea millefolium.

DISTRIBUTION.—Extreme southern tip of Illinois, near border with Missouri, Tennessee and Kentucky.

Whether Hille Ris Lambers’ (1966:605) record from California refers to P. patonkus or P. pseudopatonkus cannot be ascertained. Similarly, Hottes’ (1950) record of a “pale chocolate-brown” variety, P. patonkus var. coloradensis was not seen and its identity with 1 of the 4 species living on Achillea (P. hottesi, P. patonkusellus and the other 2 species discussed above) is not resolved here. The type of P. patonkus coloradensis Hottes is now known to be in the USNM.

SPECIMENS EXAMINED.—Paratypes: 8 apt.v.f., 13 al.v.f. and 1 altd.ny., Metropolis, Illinois, 17–IV–1930, Frison and Ross, on Achillea millefolium (INHS, KU, EOE, and M.E.MacG. coll.).